Abstract

The total cross section for the interaction of transversely polarized protons p{sub p}{sup y} and deuterons that have a tensor polarization P{sub x}{sup z} provides a null-test signal of T-invariance violation under the condition of P invariance. The relevant experiment is planned by the PAX Collaboration at the COSY accelerator with protons accelerated to the energy of 135 MeV. A modified Glauber theory is used here to calculate the differential spin observables A{sub y}, C{sub y,y}, C{sub xz,y}, C{sub z,x}, and C{sub x,z} and the differential and total cross sections for proton-deuteron scattering in the case of T-even P-even proton-nucleon interactions. This makes it possible to estimate background conditions of the planned experiment.

The cross section and several spin-dependent observables have been measured with high precision for the reaction H(d(vector sign),p(vector sign))d at 90 MeV/nucleon. Several calculations were performed based either purely on two-nucleon potentials or also including three-nucleon potentials (3NP). The cross sections are consistent with all calculations including 3NPs. However, no single calculation reproduces the analyzing powers and spin-transfer coefficients, although some spin observables are reproduced to various degrees by the different calculations. A good understanding of the spin structure of 3NP is still lacking.

Spin-dependent observables of elastic proton-deuteron (pd) scattering at intermediate energies are considered on the basis of calculations within a generalized diffraction model. The generalization in question takes into account all ten helicity proton-proton (pp) and proton-neutron (pn) amplitudes constructed on the basis of a present-day partial-wave analysis and precise deuteron wave functions derived from two alternative models of nucleon-nucleon (NN) forces. Explicit relations between the invariant amplitudes of pd scattering and input NN helicity amplitudes are found. Among other things, these relations make it possible to reconstruct unknown pn amplitudes at energies above 1 GeV on the basis of datamore » on pd scattering. The predictions of the generalized diffraction model for differential cross sections and analyzing powers are compared with the latest experimental data. Surprisingly good agreement with experimental data over a broad interval of scattering angles is found both for differential cross sections and for vector and tensor analyzing powers.« less

A novel (P-even, T-odd) null test of time-reversal invariance is discussed that allows for a accuracy of 10{sup {minus}6}. The parity conserving time-reversal violating observable is the total cross-section asymmetry A{sub y,xz} of proton-deuteron scattering. The measurement is planned as an internal target transmission experiment at the cooler synchrotron COSY-Juelich.

Recoil proton polarization observables were measured for both the p({rvec e},e{sup {prime}} {rvec p}) and d({rvec e},e{sup {prime}} {rvec p})n reactions at two values of Q{sup 2} using a newly commissioned proton focal plane polarimeter at the MIT-Bates Linear Accelerator Center. The hydrogen and deuterium spin-dependent observables D{sub scr(ll)} and D{sub scr(l)t} , the induced polarization P{sub n} , and the form factor ratio G{sup p}{sub E}/G{sup p}{sub M} were measured under identical kinematics. The deuterium and hydrogen results are in good agreement with each other and with the plane-wave impulse approximation (PWIA). {copyright} {ital 1998} {ital The American Physicalmore » Society}« less

Recoil proton polarization observables were measured for both the p(e,e'p) and d(e,e'p)n reactions at two values of Q2 using a newly commissioned proton focal plane polarimeter at the MIT-Bates Linear Accelerator Center. The hydrogen and deuterium spin-depended observables Dll and Dl, the induced polarization Pn, and the form factor ratio Gpe/Gpm were measured under identical kinematics. The deuterium and hydrogen results are in good agreement with each other and with the plane-wave impulse approximation (PWIA).